Prefastened absorbent product with releasable fasteners and flaps having welds

ABSTRACT

An absorbent prefastened product in the form of a disposable pants diaper is provided with a side closure arrangement on each side. The side closure includes front and rear side flaps having elastic portions where an inner surface of a rear side flap is overlapped and welded to an outer surface of a front side flap. Each side flap is also provided with one part of a releasable fastening system located such that the weld is located on at least one of the elastic portions and such that it lies inward of the releasable fastening system in the prefastened state. A method of forming the absorbent product is also provided, in which an overlapped attachment is formed by joining front and rear side flap members together and attaching the side flap members to an absorbent chassis member.

This application claims priority under 35 U.S.C. §119 to U.S.Provisional Application No. 60/368,978 entitled Prefastened AbsorbentProduct with Elastic Reclosable Side and Method for Producing Same andfiled on Apr. 2, 2002, the entire content of which is herebyincorporated by reference.

FIELD OF THE INVENTION

The present invention relates to an absorbent product for absorbinghuman exudate, such as a diaper or training pants and more particularly,to a disposable pants diaper which is manufactured in a closed state,i.e. a prefastened state, ready to be pulled on for wearing, yet whichcomprises side closures which can be opened and reclosed.

BACKGROUND TO THE INVENTION

Disposable training pants are well known and several different designsare available. For example, disposable training pants having front andrear portions fixedly attached together are known from WO-A-95/29657 andWO-96/31178. These designs provide adjustability of the waistband sizeto a range of users due to various elastic arrangements, but they mustbe removed like a normal pair of pants since the waist regions areformed with substantially continuous waistbands.

WO-A-00/35396 also discloses training pants with side panels which canbe elastic. The side panels are formed overlapped and attached togetherin a prefastened state by means of releasable fastening means. The sideclosures further include an adhesive between them, in order to limitaccessibility to the reclosable fastening means. The adhesive is placedso as to connect the outer flap of the overlapped flaps to the innerflap at a distal end location of the outer flap beyond the location ofthe releasable fastening means thereon. This provides a child-safetyfunction. The adhesive bond is then opened to gain access to thereclosure element. Since the adhesive must allow access to the reclosuremeans without destruction of the side panels during opening of theadhesive bond (otherwise the product would be ruined) a low bond forcemust be used for the adhesive. In preferred embodiments the glue shouldremain tacky to allow repeated opening and reclosure.

GB-A-2 267 024 discloses a prefastened absorbent product providing thepossibility of rupture of the side seams for removal or inspection ofthe product, and then the further possibility of re-closure. Theabsorbent garment has a rear portion, a front portion and a crotchportion therebetween, in which the rear portion and the front portionare united together by a seam. The seam is constituted by a line ofattachment passing through the outer edges of the front and rearportions at each side of the garment. To allow opening of the article bytearing, the front portion is provided with a line of weakening ateither side, at a location spaced inwardly from the seam. Also, are-closure possibility (i.e. releasable fastening means) is provided bytwo additional side panels on the front portion. A first edge of each ofthe side panels is fixedly attached to the outside of the front portionin the same seam as used for the rear and front portions, and a secondedge of each side panel is provided with releasable attachment meanswhich can releasably attach to the front portion.

GB-A-2 267 024 presents several disadvantages. Firstly, in order toprevent the front and rear portions of the diaper from separatinginvoluntarily due to the forces arising due to the wearer's movementwhich act directly on the seams from inside the product, the seam has tobe made particularly strong. Bonding using a force of 1000 g/inch (393.7g/cm) or more is thus required. At the same time, the line of weakeningin each of the front portions has to possess a force of rupture belowthe bonding force level in the side seams, to avoid the seam beingpulled apart when opening the diaper, yet still sufficiently high toprevent the line of weakening from being ruptured involuntarily.

The balance between these forces is difficult to achieve reliably,especially in high-speed production, particularly since the seam has toextend through three layers of material. Producing a reliable seamextending through all three separate layers of the product adds afurther difficulty to be taken into account when producing the requiredbond strength.

Still further, the releasable attachment means on the front portion sideflaps is releasably attached to the front portion of the product with astrength which should prevent the product from coming apartinvoluntarily when only the front portion side flaps are used to holdthe product together. Due to this arrangement, when the front portion isto be pulled away from the rear portion at the lines of weakening, thereleasable attachment means will exert a force on their line ofattachment in the seam unless the reclosable means is first undone. Thisforce may rupture the seam between either the front and rear portions orthe front portion and the front side flaps.

A further known solution using a flush and welded connection between twoside portions of a diaper is disclosed in U.S. Pat. No. 5,370,634. Theflush seal is subject to peel forces arising from the normal movementsof the wearer. Likewise the sealed area presents outwardly extendingedge portions which are sealed at their outermost edges, therebyproducing relatively hard combined edge portions. This is not onlyunsightly, but the hard free edge can easily come into contact with theuser's skin at the upper and or lower edges thereof, causing discomfort.

The seam produced in GB-A-2 267 024 also has further disadvantages inthat not only two, but three panels are combined with their outer cutedges lying outside the seam. As in U.S. Pat. No. 5,370,634, thisproduces a stiff edge arrangement, since the seam lies just inside theedges of the three panels. This again can affect comfort when thewearer's clothes press against the hard seam edge for example, as wellas resulting in discomfort at the upper and lower edges of same. Theflush seams in both U.S. Pat. No. 5,370,634 and GB-A-2 267 024nevertheless allow production in a flattened condition.

WO-A-99/65438 discloses a further garment arrangement in which the outeredges of a front waist section are overlapped by two rear side panels ofa rear waist portion. The outer ends of the front waist portion arefixedly attached by means of passive bonds to the inner surface of therear waist portion and to the leg elastic at the rear part of thegarment. The rear side panels further comprise two different type ofreclosure means in the form of hook and loop fasteners which arereleasably secured to the front waist portion. In this way, the passivebonds provide added shear strength to assist the reclosure means. Suchan arrangement can provide a stable side closure system as a result ofthe passive bond locations. However such products suffer from a lack ofadaptability and poor comfort and must rely on the waist band to providesome limited elasticity.

The invention has the object of providing an absorbent product with animproved side closure construction which allows low attachment forces tobe used in releasable and non-releasable (i.e. fixed) attachment areas,while maintaining a closure arrangement which is reliable yet whichallows a high degree of elasticity in the side closure and at the sametime providing a good fit on the wearer.

The present invention also seeks to provide a method for producing anabsorbent article of the type described above which obviates theproblems with a flush seam and yet which can be easily formed in a flatcondition during production.

SUMMARY OF THE INVENTION

In accordance with the invention, the absorbent product comprises atleast two sets of closure means, a first closure means which forms afixed attachment between the elastic side flaps of the front and rearportions by means of a weld, and a second closure means which is in theform of a releasable fastening means.

The fixed attachment by means of a weld refers to a type of permanentattachment between two parts which is not intended to be openedunintentionally and once opened cannot be reformed. The weld ispreferably formed by ultrasound welding or by heat welding, but otherforms of welding may be used. The weld may be such that it can be openedby applying peeling forces which results in peeling apart (typicallywith some tearing) of the weld, or may be made at a strength such thatthe weld remains substantially intact while a specific part of the sideflap adjacent the weld will be made to rupture.

The releasable fastening means is, on the other hand, a type ofattachment which is capable of being opened and re-closed. Suchreleasable fastening means comprises two members which cooperate to givea releasable attachment when a relatively light pressure is appliedforcing the two members together. Such releasable attachment means maybe of the mechanical type. One form of such a mechanical fastener is thehook and loop type, whereby one member comprises material having hooksor other projections thereon (e.g. mushroom-head projections), and theother member comprises complementary loops, receiving apertures orreceiving spaces. Nonwoven material can for example by itself form aloop member, whereby the hooks of the complementary hook part canreleasably attach to the nonwoven material. Many other types ofreleasable mechanical fasteners are known to one skilled in the art. Afurther type of releasable fastener may be an adhesive type of fastener,whereby a pressure sensitive adhesive is coated on one component and acomplementary component is provided to which the pressure sensitiveadhesive may adhere. Such releasable attachment means are well known inthe field of absorbent products.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be explained in more detail with reference tocertain non-limiting embodiments thereof and with the aid of theaccompanying drawings, in which:

FIG. 1 shows a plan view of an absorbent product according to theinvention in an opened-out condition, before the side flaps of thediaper have been fixedly attached together,

FIG. 2 shows a side view of an absorbent product according to theinvention similar to that in FIG. 1, in which the side flaps having beenfixedly attached together by means of a weld,

FIG. 3 shows a view from above of an absorbent product according to FIG.2, showing the connections of the various layers before rupture of theside attachments,

FIG. 4 shows a view similar to that in FIG. 3, of a product in which thefront side flaps are additionally provided with lines of weakening whichhave been ruptured,

FIG. 5 shows a cross-sectional view through a laminate material whichmay be used in the front and/or side flaps,

FIG. 6( a)-FIG. 6( d) show a series of steps, from top to bottom in thedrawing, exemplifying the method of the present invention,

FIG. 7 shows a view from above, of one half of a further embodiment of aside closure arrangement,

FIG. 8 shows a further embodiment in a view from above similar to thatin FIG. 7, depicting the overlapped portions of the side flaps,

FIG. 9 shows an embodiment of the second (laterally outer) portion ofthe outer side flap in FIG. 8, in a view from above and enlarged,

FIG. 10 shows a further embodiment of the invention in a view from abovesimilar to FIG. 8,

FIG. 11 shows a further embodiment of the invention in a view from abovesimilar to FIG. 10,

FIG. 12 shows a further embodiment of the invention in a view from abovesimilar to FIG. 11,

FIG. 13 shows a side view of the embodiment in FIG. 12,

FIG. 14 shows a side view of a further embodiment of the overlapped sideflaps,

FIG. 15 shows a further embodiment in a view similar to that in FIG. 14,

FIG. 16 shows a still further embodiment of the invention in a viewsimilar to that shown in FIG. 15,

FIG. 17 shows an embodiment of the invention similar to that shown inFIG. 15, depicting particular dimensions,

FIG. 18( a) and FIG. 18( b) show two steps (a) and (b) of a test methodfor measuring peel strength, and

FIG. 19 shows a further embodiment of the invention in a view similar tothat shown in FIG. 17, provided with an additional child-safety closure.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The absorbent product of the present invention is used for absorbinghuman exudate, such as a diaper or training pants. In particular, thepresent invention relates to absorbent pants of the disposable type,i.e., those which are to be discarded when soiled and are not intendedto be washed and reused. In FIG. 1, the absorbent product is shown in aflattened state with the inner side of the absorbent product uppermost.The absorbent product comprises three portions, a rear portion 1, afront portion 2 and a crotch portion 3 extending between these portions.The length of the portions is not precise, but generally each of theseportions occupies about one third of the length of the product in aflattened condition. The rear portion 1 has an edge 42 at its outer endand the front portion 2 has an edge 43 at its outer end. In the depictedcondition, a longitudinal axis Y-Y and a lateral axis X-X are shown,these axes extending generally perpendicular to each other, thelongitudinal axis extending generally between the middle of the rearportion 1 of the product and the middle of the front portion 2 of theproduct.

Throughout the present specification and claims, reference has been madeto front and rear portions of an article. The rear portion of an articleis that portion which is intended to be placed at the rear of a wearerin use, whilst the front portion is that portion intended to be placedat the front of the wearer during use. However, it will be apparent toone skilled in the art that the front and rear portions can be invertedand that the front and rear side flaps described below may thus befitted to either of the front and rear portions without altering theunderlying nature of the invention.

It should be observed that FIG. 1 depicts the absorbent product in acondition before the product has been fixed together in its final(prefastened) state, i.e. before the front side flaps 6, 7 and rear sideflaps 8, 12 and 9, 13 have been overlapped and fixedly as well asrefastenably attached together (the overlapped and attached arrangementwill be explained further below).

The absorbent product includes an absorbent product chassis membercomprising at least a back sheet 4 and a top sheet 5. The back sheet 4is preferably impervious to liquids. The top sheet 5 is preferably aliquid permeable layer. Materials suitable for these layers are wellknown and typically the back sheet layer 4 may be formed entirely fromor including a polyethylene (PE) film. Such a back sheet may for examplebe a textile-like back sheet formed from a laminate of PE and spunbondedpolypropylene (PP) nonwoven material, where the PE has for example asurface weight between 12 g/m² and 20 g/m² and the PP has a surfaceweight between 10 g/m² and 20 g/m². The top sheet layer 5 may be formedfrom a nonwoven polypropylene (PP) fibrous web (e.g. a spunbonded PPweb) for example. Sandwiched between the back sheet layer 4 and the topsheet layer 5 is an absorbent core 37, the absorbent core comprising abatt of e.g. cellulosic fibres, preferably mixed with superabsorbentmaterial in a homogeneous, or layered distribution or in a distributionwhich varies in the depth direction and/or in the major plane of thecore. The absorbent core may take many shapes and forms and may includeseveral layers with differing properties so as to improve absorptioncharacteristics. The back sheet and top sheet layers 4, 5 are preferablyof equal size and are preferably sealed to each other around theirperipheries in a manner known in the art.

Elasticated waistband means 38, 39 are preferably provided at each endof the absorbent product chassis member and serve to provide a means ofimproved comfort, fit and containment in the product. Such elasticatedwaistband means are well known in the art. The elastic waistband means38, 39 are shown as lying outside the absorbent core 37, although itwill be understood that they may partially cover the area bounded by theabsorbent core 37. Similarly, the waistband means may extend up to thelongitudinal side edges 40, 41 and/or up to the end edges 42 and 43.

Further known elements can of course also be included in the absorbentproduct even though these are not shown in the present Figures. Suchelements may include, for example leg elastics to provide a better fitaround the wearer's upper legs, standing gathers, edge gaskets as wellas other barriers and seals to prevent leakage.

Two front side flaps 6 and 7 are provided. Each side flap is formed as asingle piece in the embodiment shown in FIG. 1, although a plurality ofpieces laterally or longitudinally in series, or a plurality of layersor panels e.g. in series or partially or fully overlapping, may be usedto form each side flap. In a preferred embodiment, a single piece may beused comprising a plurality of layers, one of which is elastic. The sideflaps are each formed with an elastic portion, such as provided by anelastic laminate. The elastic portion may extend so as to cover thewhole area of flaps 6 and 7, but preferably should at least cover thearea thereof which lies outside the edges 40, 41 of the chassis up tothe laterally outward edge of the flaps 6 and 7. Each front side flap 6,7 is fixedly attached (by welding, adhesive, stitching or other knownmethods of fixed attachment) to a respective side of the chassis memberat attachment locations 35 and 36, preferably on to the external surfaceof the back sheet 4 as shown. However, it should be understood that theside flaps 6, 7 may be attached to the internal or external surface ofthe top sheet 5 or the internal or external surface of the back sheet 4if desired, or to both the back sheet 4 and top sheet 5. A still furtherpossibility is that either the back sheet 4 or the top sheet 5, or apart thereof, may itself be included as part of the side flaps and thusform one of the layers of material constituting the side flaps 6, 7, 8,12, 9, 13, as explained below in respect to a further embodiment.

At the rear portion of the absorbent chassis, there are two rear sideflaps 8, 12, 9, 13. In the preferred embodiment shown, the rear sideflaps are separate flaps comprising a first portion 8, 9 and a secondportion 12, 13. The second portion 12, 13 is fixedly attached (bywelding, adhesive, stitching or other known methods of fixed attachment)to the respective first portion 8, 9 at attachment locations 26 and 24respectively on the external surfaces 20, 20′ of the first portions(FIG. 3). Each second portion 12, 13 is fixedly attached at a locationlaterally outwardly of the attachment locations 23 and 27, such that thesecond portions 12, 13 lie laterally outwardly with respect to the rearside flap first portions 8, 9.

Each of the second portions 12, 13 in such a structure is not intendedto lie directly against the skin of the wearer (see FIG. 3 explanationbelow) and thus the second portions 12, 13 may be formed stiffer thanthe first portion, e.g. by using a stiffer material for the secondportions 12, 13. The second portions are each preferably formed to beinelastic. Being inelastic allows the second portions 12, 13 to providea more stable panel structure while avoiding any folding or wrinklingeffects for example.

An arrangement with two portions 8, 9 and 12, 13 is not however limitingfor the invention, as long as a portion of the flaps are elastic. Thus,the rear side flaps may each be composed of only a single portion, or ina further embodiment of three or more portions. Each of the rear sideflaps is fixedly attached (by welding, adhesive, stitching or otherknown methods of fixed attachment) to a respective side of the chassismember at attachment locations 23 and 27, preferably on the externalsurface of the back sheet 4 as shown. However it should be understoodthat the side flaps 8, 12 and 9, 13 may be attached to the internal orexternal surface of either the top sheet 5 or the back sheet 4 asdesired, or to both the back sheet 4 and the top sheet 5.

In the preferred embodiment shown using two portions, at least asubstantial part of the area of the first portion 8, 9 is formed ofelastic material, and preferably the whole area of the first portion 8,9 is formed of elastic material, such as an elastic laminate material.In a more preferable embodiment which avoids waste of elastic materialwithout reducing elasticity, the elastic material is placed in that areaof the first portion 8, 9 lying outside the attachment zone 23, 27 up tothe attachment zone 24, 26 (i.e. in the portion of the flap which isfree for elastic extension).

Each of the rear side flaps carries one member of a releasable fasteningmeans 10, 11 at its outer end. Each member 10, 11 of the releasablefastening means in the shown embodiment is preferably constituted by ahook-type member preferably in the form of a strip of hook-type materialextending between the upper and lower edges of the second portions 12and 13 of the rear side flaps. Although a single strip is shown, severalstrips may instead be used, which can then be intermittently spaced fromone another, preferably in a vertical direction. Similarly, the verticalextent of the members 10, 11 is shown as preferably extending almost thewhole longitudinal length of the side flap portions 12, 13 leaving asuitable distance from the upper and lower edges of the flap portionsfor manufacturing tolerances. Preferably the longitudinal length ofmembers 10, 11 on the rear side flaps is between 25% and 75%, preferablybetween 25% and 60%, of the longitudinal length of the front side flaps6, 7 at the intended attachment location thereon. This is intended tosubstantially avoid any contact of the member 10, 11 with the body. Themembers 10, 11 may however extend the whole length of the flap portions12, 13.

It is however preferred that where hook and loop members are used, theloop member of the releasable fastening means should have a largersurface area than the hook member.

Similarly, the second portions 12, 13 of the rear side flaps may beformed entirely of nonwoven loop material, requiring thereby that a hookmember be positioned on the outer surface of the inner (front) side flapin the overlapped condition.

These members 10, 11 are adapted to releasably engage with correspondingmembers 15, 16 of the releasable fastening means on the front side flaps6 and 7. Since the second portions 12, 13 are preferably made relativelystiff compared to the first portions, as explained above, this willallow the second portions 12, 13 to provide a more stable base for thestrip members 10 and 11 and thus can assist in forming a more reliablyattached and more easily handled releasable fastening arrangement.

In the embodiment shown, the front side flaps themselves include anexternal covering material to which the members 10, 11 can releasably befastened, although, if desired, separate additional strips of material,e.g. loop material pieces (not shown) may be added. An example of anelastic laminate suitable for this purpose will be explained furtherbelow with regard to FIG. 5.

Although it is shown in the drawings that the front and rear side flapsare separate pieces from one another, it will however be understood bythe skilled person that the front and rear side flaps on each respectiveside of the chassis member may be formed as a single continuous member,attached along the entire respective side edges 40, 41 of the chassismember. Alternatively, the rear side flaps and the front side flaps mayremain as separate members in the manner shown in the Figures, but maybe extended in the longitudinal direction to simply overlap each otherin the area of the crotch region 3.

Similarly, although the rear side flaps 8, 12 and 9, 13 and the frontside flaps 6, 7 are shown as being separate members fixedly attached atrespective longitudinal side edges 40, 41 of the chassis member rearportion 1 and front portion 2, the rear side flaps could alternativelybe combined as a single separate piece (not shown) extending laterallyacross the rear portion 1 and extending as side flaps beyond thelongitudinal side edges 40, 41 of the chassis member. Similarly thefront side flaps 6, 7 could be formed by a single separate piece (notshown) attached laterally across the front portion 2 of the chassismember.

In order to form the absorbent product of the invention, a fixed,preferably welded attachment is provided between the front side flaps 6,7 and the respective rear side flaps 8, 12 and 9, 13 in the prefastenedcondition. In order for this to occur, the chassis member is preferablyfolded at some stage, substantially along or parallel to the lateralaxis X-X, such that the front and the rear side flaps can overlap. In analternative embodiment, the front side flaps and rear side flaps canhowever be made to first overlap and then be welded, before folding ofthe chassis member, and then the rear and/or front side flaps attachedto the chassis. This is also explained with respect to the various stepsand various order of steps of manufacture described further below.

The form of the overlap is an important factor in providing good seamsecurity, good comfort and allowing a high degree of elasticity. Thepreferred overlap is shown externally in FIG. 2 and from above in moredetail in FIGS. 3 and 4 for example. As these Figures show, each one ofthe front side flaps 6, 7 is fixedly welded to a respective one of saidrear side flaps 8, 12, and 9, 13 such that the outer surface 18, 18′ ofeach one of the front side flaps 6, 7 lies against the inner surface 19,19′ of a respective rear side flap 8, 12, and 9, 13.

In FIGS. 2 and 3, it can be seen that the area of the weld 21, 22 isformed at the end portion of the first portions 8, 9 and the endportions of the corresponding front side flaps 6 and 7, so as to fixedly(i.e. non-releasably) join these portions together. In this regard theterm “end portion” refers to that portion of each front side panel whichoverlaps each rear side panel first portion 8, 9. Such an overlap may beon the order of 0.5 to 3.5 cm and, preferably, between 0.5 and 2 cm.

In the closed condition as shown in FIG. 2, it can be seen that thereleasable fastening means 10, 11 on the second portions 12 and 13 arealready in contact with the corresponding fastening members 15, 16 ofthe outer surface 18, 18′ of the front side flaps 6, 7. Thus a strongforce is provided preventing separation of the front and rear sideflaps, including the force provided by both the releasable fasteningmeans 10, 11, 15, 16 and the welds 21, 22.

Since the flaps 6, 7 lie against the wearer's skin, it is preferable ifthe outer edges of these are formed so as to be soft. Where, forexample, the front side flaps 6 and 7 are formed of an elastic laminatehaving nonwoven outer surface material such as spunbonded PP, this edgecan clearly be soft without the addition of further outer end edgearrangements.

Moreover, due to the overlapping relationship of the front and rear sideflaps, with the inner surface of one lying against, and welded to, theouter surface of the other, the forces acting from the wearer duringmovements (e.g. sitting, standing, etc.) to separate the front and rearside panels at the welds 21, 22 are not peeling forces as in much of theprior art, but instead are shear forces. Since it is easier to rupturean area of fixed attachment such as a seam by peeling than it is byapplying shear forces, it will be apparent to one skilled in the artthat it is extremely difficult to rupture the area of attachment in thepresent invention by the movements of the body. Therefore, a reliableseal is provided.

The provision of a reliable seal by this overlap structure thus allowsattachment forces to be used which have a force value against peeling ofless than 1000 g/inch (394 g/cm), as measured by the method disclosed inGB-A-2 267 024. Thus, attachment forces having a peeling strength forceof less than 350 g/cm and, preferably, less than 300 g/cm, and morepreferably, less than 200 g/cm can be used.

At the same time, it will be observed that in the preferred embodimentsshown only two panels are included in the area of the welds 21, 22,namely the front side flaps 6, 7 and the rear side flap first portions8, 9. This allows a reliable and easily controllable seam to be made.Furthermore, the product is more comfortable to handle and wear thanproducts where the front and rear parts of the absorbent pants areattached at their sides in a flush arrangement, since there are norelatively rigid parts pointing outwardly. As discussed above, furtherpanels can of course also be included.

In one embodiment, the second portions 12, 13 of the rear side panelsare fixedly attached (by welding, adhesive, stitching or other knownmethods of fixed attachment) at attachment locations 26, 24 to the firstportions 8, 9, which locations 26, 24 are laterally outward of the areasof welds 21, 22 as seen with respect to the lateral axis and withrespect to the rear portion 1 of the chassis. However, it will beunderstood that the attachment locations 24, 26 may be laterally inwardof the areas of the welds 21, 22 if desired, whilst still allowing onlytwo panels to be used in the welds 21, 22. This can be arranged forexample by fixedly attaching the panels 12 and 13 after first formingthe welds 21, 22. The attachment area of portions 12 and 13 to portions8 and 9 could however also be made to coincide with the welds 21 and 22and the welds 21, 22 may also be made so as to extend through all threepanels (i.e. front side flaps 6, 7, rear side flap first portions 8, 9and second portions 12, 13). This is easily possible, although lessdesirable, since the strength of the weld for resisting peel forces neednot be so great due to the provision of the overlapped inner and outersurfaces of the side flaps. It is preferred that no more than fourmaterial layers should be included in the welded regions, however,preferably no more than three, and most preferably only two materiallayers should be included. In whichever way the weld 21, 22 is formed,the weld is preferably placed laterally inwardly with respect to thereleasable fastening means 10, 11 at the outer ends of the rear sideflaps proximate the outer end edges 44, 45 thereof, such that the weld21, 22 in each of the rear side flaps 8, 12, 9, 13 lies laterallyinwardly with respect to the releasable fastening means 10, 11positioned on its respective rear side flap.

In other words, for the embodiment shown in FIG. 3, where the rear sideflaps 8, 12, 9, 13 overlap the front side flaps 6, 7, the rear flapsform an outer side flap and the front side flap forms an inner side flapof the whole side closure structure. The releasable fastening means 10,11 is thus positioned closer to the outer edge 44, 45 of the outer flapthan the weld 21, 22.

Also, the position of the weld with respect to the elastic portions is afactor in giving a maximum degree of elasticity to the side closurestructure. In this regard the weld 21, 22 should preferably bepositioned proximate the laterally outer edge of the elastic portion ofat least one of the front and rear side flaps 6, 7, 8, 12, 9, 13. Inthis way, there is little or no elastic material which remains inactiveoutside the welds 21, 22 and thus the maximum amount of elastic materialis available for providing the required elasticity in the side closures.

In the embodiment shown, the welds 21, 22 are positioned proximate thelaterally outer edge 48 of each of the front side flaps 6, 7, each ofthe front side flaps being elastic. The welds 21, 22 are also placedproximate the laterally outer edge 47 of the elastic portion (firstportion 8, 9) of each of the rear side flaps. In this way, the area ofelastic material which is elastically inactive is kept to a minimumthereby allowing the maximum lateral extent of elastic material to befully used in both front and rear side flaps. In terms of the meaning“proximate” in this regard, this means less than approximately 1.5 cmfrom the end edge of the elastic portion. It is, however, preferred ifthe distance is less than approximately 1 cm and still more preferableif the distance is less than approximately 0.5 cm.

As shown in FIG. 2, the weld 21 extends between the upper edge of frontside flap 6 and the lower edge of the same. Preferably, the area of theweld extends the entire distance between these upper and lower edges andthe line of weld tool application may even extend beyond the upper andlower edges. The attachment area may however be shorter, although theadvantage with an extension all the way between the upper and loweredges is that the product has no loose side flap corners which maypossibly fold over and become unsightly during storage. Similarly, amore secure/stable fit during use is obtained by arranging the weld toextend all the way between the upper and lower edges, which can beparticularly relevant when the elastic portions are placed between thewelds 21, 22 and each of the side edges 40, 41.

When the absorbent product, in the form of disposable pants as shown inFIG. 2, are to be inspected to check whether they have been soiled, orwhen they are to be removed entirely, it is convenient if the entirepants do not have to be removed over the wearer's legs and feet. Thus,the areas of attachment provided at welds 21, 22 simply have to beruptured by being peeled open. This destroys the welded seal and doesnot allow reclosure thereof. This can be done in any suitable way,preferably however by gripping and pulling rearwardly the free edge ofthe side flap second portion 12, 13 lying in front of the releasableattachment member 10, 11 while at the same time holding the front flap6, 7 with the fingers of the other hand. The attachment welds 21, 22will thus be peeled open vertically by the application of peeling forcesthereto.

In an alternative embodiment shown in FIG. 4, a line of weakening 33, 34can additionally be provided in each front side flap 6, 7, extending atleast part way between the upper and lower edges of the respective frontside flaps 6, 7 and at a location laterally outwardly of the respectiveattachment area 21, 22. In a manner similar to that described above, thefront side panels and the rear side panels are separated, this timehowever by rupturing the front side flaps 6, 7 along the lines ofweakening 33, 34. The lines of weakening in this regard may also beformed by the outer margin of the areas of welds 21, 22, for example, asa result of the welding process in which the outer edge of the weld canbe made to provide a weakened area on the inner, front side flap 6, 7.

Whichever of the structures in the various embodiments is used, theabsorbent pants will become separated at the side portions by rupture(either by peeling and/or tearing of the seals and/or by tearing of thefront side flaps).

Once inspected, if the absorbent product is not soiled it can bereattached while on the user by re-closing it. For this re-closure, thereleasable fastening means 10, 11, 15, 16 are used, whereby therespective first member 10, 11 of the releasable fastening means issimply pressed into contact with the outer surface 18, 18′ provided withthe second member 15, 16 of the releasable fastening means. If desired,these releasable fastening members 10, 11, and 15, 16 may be attachedand detached from one another several times.

While the side flaps may be formed of any suitable structure includingan elastic portion, a preferred structure is one having nonwovenmaterial 30, 32 on both the inside and outside surfaces thereof. In thisway, the side flaps feel relatively comfortable against the skin of thewearer and at the same time provide an external surface to which onemember 10, 11 of the releasable fastening means can attach. In a furtherembodiment (not shown) one or more of the layers of nonwoven materialcould be constituted by a nonwoven layer which is integrally included aspart of the top sheet 5 and/or back sheet 4 structure.

In a particularly preferred embodiment, the front side flaps 6, 7 and/orthe rear side flaps (i.e. portions 8, 9 only) may comprise an elasticlaminate as shown for example in cross-section in FIG. 5. In such alaminate, a central elastic lamina material 31 is used. Such an elasticlaminate may have an elastic extensibility at least in the lateraldirection of over 100%, preferably over 150%, and even more preferablybetween 200% and 350%. Elastic materials able to produce this elasticityin the final laminate are well known in the art of absorbent products.These may include for example, elastomers made from block copolymerssuch as polyurethanes, copolyetheresters, polyamide polyether blockcopolymers, EVAs (ethyl-vinyl-acetates), elastomeric styrene-butadienecopolymers, tetrablock copolymers, includingstyrene-poly(ethylene-propylene) elastomeric block copolymers,polyamides, or natural and synthetic rubber materials, etc. One suitableelastomer is for example Extraflex™ CEX 802WR having a surface weight of54 g/m², available from Tredegar film products.

Due to the overlapping nature of the front and rear side flaps, whichmay occupy between 0.5 cm and 3.5 cm lateral length in each sideclosure, the overlapped area will be relatively inelastic. Without highelasticity material constituting the side flap and having at least 100%elasticity (i.e. can be stretched elastically by more than 100% comparedto its original length without substantial permanent strain), theelastic material of the respective side flaps lying between theoverlapped panels and the edges of the chassis is not able to fully meetthe requirements for good fit and comfort for all intended users.

Inelastic members used in this invention such as nonwoven materials, maycomprise a continuous or discontinuous sheet, web, layer or fabric forexample, which member can be stretched elastically by only smallamounts, normally on the order of between 1 to 15%, but typically lessthan 10%. Such materials may be spunbonded, carded nonwovens ormeltblown materials. The fibres can be e.g. polyolefins such aspolypropylene or polyethylene. The fibres can also include mixtures ofdifferent polymers. Suitable nonwoven materials can also include severaldifferent nonwoven layers such as spunbond-meltblown-spunbond (SMS)laminates. A concrete example is a spunbonded material of polypropylenefibres where the material has a surface weight which can be arranged tolie between 12 and 30 g/m², and having a fibre thickness of between 0.5and 5 dtex.

Attached on either side of the elastic lamina 31 in a stretchedcondition are relatively inelastic nonwoven material webs 30, 32. Afterattachment, when the elastic laminate is allowed to return to itsrelaxed state, the attached nonwoven webs contract and form a lightlycorrugated surface, with air pockets between the corrugations, thusproviding a comfortable feel.

In a variation (not shown) of the embodiment depicted in FIG. 5, thenonwoven material layer 30 or 32 of the side flap may be formed by anextension of the material in the top sheet 5 and/or the back sheet 4.For example, the back sheet 4 may be formed of a laminate structure (notshown) of a nonwoven material layer and a polymeric film material layer,whereby an extension of the nonwoven material layer of the back sheetcould then be used to form either layer 30 or layer 32 of the side flap.Similarly, where one outer layer 30 or 32 is formed by nonwoven materialof, e.g., the top sheet, the other outer layer 32 or 32 may be formed bynonwoven material of the back sheet or a separate sheet of material.Additionally, whilst the use of nonwoven materials is preferred, otherinelastic materials can of course be used both in the top sheets and/orback sheets and then be extended so as to form at least one of thenon-elastic materials in the side flaps.

The product of the invention may be formed in a variety of ways.However, in accordance with the present invention, a preferred methodhas been devised which allows the areas of attachment 21, 22 between thefront and rear side flaps to be formed easily with the product lying ina flat condition. In this way, forming the areas of attachment 21, 22 isfacilitated, especially where the area of attachment is formed bywelding.

FIG. 6( a)-FIG. 6( d) shows a series of operations which are carried outto produce an absorbent product. Only one side of the product is shownalthough the operations on the opposite side are the same. The order ofoperations, although shown as steps (a) to (d), can however be varied tosome degree as will be understood from the following.

In order to aid understanding, like reference numerals have been used todenote corresponding parts described with respect to the product of theinvention, however with the addition of the letter “a” after thenumerals.

The production flow is intended to be from step (a) to step (d) as shownin FIG. 6( a) to FIG. 6( d). In step (a) a first portion 9 a of a firstside flap member (e.g., rear side flap) is shown with its inner surface19 a uppermost and fixedly attached to a second portion 13 a. Theattachment of these two portions can occur at the moment they are placedone upon the other (e.g., by adhesive) or it can occur subsequentlythereto such as by welding, for example.

In step (b), an absorbent product chassis member having a top sheet 5 ashown uppermost and a back sheet 4 a underneath, is laid on the firstportion 9 a and fixedly attached thereto at an area 23 a at one endportion of the chassis member, such that it extends laterally outwardlyfrom a side edge 40 a of the chassis member. It is also possible, in analternative embodiment (not shown), to arrange the first portion 9 a tobe located between the top sheet 5 a and the back sheet 4 a and thusconceal the joint 23 a between the top sheet 5 a and back sheet 4 a.This can be done for example by first laying down the back sheet 4 a,then attaching the flap portion 9 a, then applying the absorbent coreand then adding the top sheet 5 a.

As will also be clear, the chassis member may however be placed first onthe production line, followed then by the flap member 9 a, 13 a ifdesired, i.e., a reversal of steps (a) and (b). A first portion of areleasable fastening means 11 a is added as a strip or the like, asdescribed previously, to the end of the first (rear) side flap. This maybe in either step (a) or step (b) for example.

In step (c) the second side flap member 7 a is added (e.g., the frontside flap 7), with its inner surface 17 a upwards and its outer surfacefacing downwards, whereby the second member 15 a of the releasablefastening means is on that downward facing side. In this condition, theinner surface 19 a of the first side flap member 9 a, 13 a lies in anoverlapping relationship against the outer surface of the second sideflap member 7 a in a flat (i.e., unfolded) state. The fixed attachmentarea 21 a is then formed, for example by welding, at the rectangulararea indicated by 21 a, whereby it is noted that the weld extendsbetween the upper and lower edges of the first and second side flaps.

At this stage, first end portion 1 a (e.g., the rear end portion 1) andthe second end portion 2 a (e.g., the front end portion 2) of thechassis member are still in a flat condition. Thus, in order to form theclosed product, the portion 2 a needs to be folded on to the portion 1 aand the second flap member 7 a needs to be fixedly secured to the secondend portion 2 a.

This folding operation can be done either by starting at step (c) andthen in step (d) folding portion 2 a onto portion 1 a, and then foldingthe second flap member 7 a over the first flap member 9 a, 13 a and thusinto contact with the outer (back sheet 4 a) surface of end 2 a.Alternatively, the second flap member 7 a can be folded over the firstflap member 9 a, 13 a and then the end portion 2 a folded over on top ofthe outer surface of the second flap member 7 a, and thus into contactwith the inner (top sheet 5 a) surface of end portion 2 a.

In either condition, the end of the second flap member 7 a is thenfixedly secured at location 36 a to the second end portion 2 a of thechassis member. Preferably, such securement is performed by usingadhesive on the cooperating surfaces of the flap member 7 a and thesecond end portion 2 a of the chassis member, although other methods offixed attachment may also be employed.

In a still further embodiment, the attachment of the first flap member 9a, 13 a to the second flap member 7 a at the attachment area 21 a (i.e.,as in part of step (c)) can be performed without the chassis memberbeing present. The chassis member can then be fixedly attached atattachment location 23 a and attachment location 36 a.

In a still further embodiment, before performing step (d), the flap 7 acan first be folded before the chassis itself is folded, and only thenattached at area 36 a. In this way, the attachment 36 a is positioned onthe inside of the product and not visible.

FIG. 7 shows a further embodiment of the present invention in a viewfrom above, similar to that in FIG. 3, wherein however only one side isshown (the other side being substantially a mirror image) and whereinthe rear part 1 of the diaper is lowermost. In FIG. 7, the first sideflap portion 8 and the front side flap 6 is elastic between theattachment location 27 and the end edge 47 and the attachment location35 and the end edge 48 respectively, side flap 6 and first portion 8preferably being formed entirely of an elastic laminate. The secondportion 12 is preferably entirely inelastic. The front side flap 6 has,on its outer surface and fixedly attached thereto, one member 46 of areleasable fastening means in the form of a strip, the strip beingelongate in the longitudinal direction Y-Y (i.e., in a planeperpendicular to the plane of the paper in the same way as members 10and 11 as shown in e.g. FIG. 2 are elongate). The cooperating member 10of the releasable fastening means is fixedly attached to the inelasticportion 12 of the rear side flap.

The weld 21 thus passes through the elastic portions proximate thedistal (laterally outward) ends thereof. In this way, only twocomponents need be attached together. Similarly, since the weld 21 is atthe ends of each elastic portion in the small overlapped area betweenend edges 47 and 48, the elastic flap material between weld 21 andattachment location 27 remains active for elastic extension. In thefirst side flap 6, the portion thereof remaining active for elasticextension is, in this case, that portion which extends betweenattachment location 35 and the location 49 at which the laterally innerend of strip member 46 is attached to the side flap 6.

To further improve the amount of elastic material available for elasticstretching, the non-elastic portion of the side closure, i.e. betweenline 49 and weld 21, is preferably kept to a minimum. The distancebetween line 49 and weld 21 should preferably be configured such thatthis distance occupies a maximum of one third of the elastic part of theside closure (i.e., the distance between attachment location 35 and line49 added to the distance between line 21 and attachment location 27, inthe unstretched condition). Preferably, this distance should be between0.5 and 3.5 cm. Similarly, in the unstretched condition, the length ofthe elastic portion (that portion between attachment locations 35 and 49and between location 27 and weld 21) of the whole side closure, shouldpreferably be greater than 75% of the length of the side closure (i.e.,the distance between attachment locations 27 and 35 in the prefastenedcondition). The elastic extensibility of the side closure betweenlocations 27 and 35 including the elastic and inelastic parts joinedtogether, starting from a non-stretched starting length of the sideclosure, should preferably be greater than about 80% and most preferablygreater than 100%.

If the member 46 is not present, the member 10 should thus attachdirectly to the outer surface 18 of side flap 6, and then thenon-elastic portion would be between weld 21 and the location wheremember 10 attaches to the outer surface 18.

The member 10 can, for example, be of loop material and the cooperatingmember 46 of hook material, or vice versa. Inwardly facing hooks arehowever, preferable, since this allows easier disposal in a closedcondition. It is also possible to construct the inelastic second portion12 entirely of loop material and then construct member 46 of hookmaterial to engage therewith.

FIG. 8 and FIG. 9 show a further embodiment of the invention, similar tothat described in relation to FIG. 7, whereby the inelastic portion ofthe rear side flap (second portion 12) is formed not by a separate pieceof material being attached to the outside of the first portion as in theembodiments of, for example, FIGS. 1 to 4, but instead by the elasticlamina 31 of the elastic laminate material (see also FIG. 5) beingterminated at an end 50 which lies laterally inside end 44. Thus,distance “a” is inelastic and corresponds to the inelastic portion 12.

In the embodiment shown in FIG. 10, this differs from that shown anddescribed with respect to earlier embodiments in that the inelasticsecond portion 12 is located and fixedly attached to the inner surface19 of first portion 8.

In the embodiment shown in FIG. 11, the second portion 12 is formed as aU-looped strip, whereby the open ends of the “U” are fixedly attached,e.g., by welding or adhesive for example, to the laterally outer end 47of the first portion 8 at attachment locations passing through line 51.In this way the second portion 12 will be more safely attached to thefirst portion 8 and the risk of separation of the portions 8 and 12 isreduced at the same time as providing a softer outer edge.

In the embodiment of FIG. 12, a further possible form of the inelasticsecond portion 12 is depicted, in the form of a gripping pocket whichallows the fingers of a hand to be inserted into the U-shaped loop foropening or refastening the product (the U-shaped loop being attached ate.g. its upper and lower longitudinal edges for example as shown in FIG.13 at fixed attachment locations 52 and 53 (e.g. welds)). In this way,the user can insert one or more fingers between the attachment areas anduse this as a gripping means to open the reclosable fastening means 10,46 and/or as a means for peeling or tearing the first portion 8 awayfrom the inner flap 6 at the weld 21. A user can similarly insert afinger between the round end 54 of the loop and the attachment locations53 or 52 if the loop is made sufficiently long. As will also beapparent, either one of the two fixed attachments 52 or 53 could beomitted, which still allows a finger to be inserted into one corner areaof the pocket. Many further modifications of such a gripping pocket byalternative means and locations of attachment will be apparent to askilled person.

In the embodiment of FIG. 14, which is a partial side view of the sideclosure showing overlapping panels 6 and 8, 12, the inelastic portion 12is made to be gradually reduced in length moving laterally outwardlyalong the rear side flap 8, 12 to the end edge 44, so as to provide alaterally outwardly tapering lower edge. The member 10 may howevermaintain an elongate rectangular form. In this way a smoother transitionbetween the lower edge of portions 8 and 12 is provided (when comparedto e.g. the FIG. 1 embodiment) which provides a comfort improvement onthe wearer's legs and reduces the amount of waste material at the sametime.

The embodiment of FIG. 15 is similar to that of FIG. 14, differinghowever in that the member 10 is also made to taper towards thelaterally outer edge 44. In this way, the second portion 12 can maintainthe advantages described above and the member 10 can be spaced from theedges of the second portion 12 yet still use the maximum area forproviding an attachment surface, which is particularly useful inallowing a more secure fastening when the weld 21 is broken.

In the FIG. 16 embodiment, the fixed attachment in the form of weld 21is formed by a series of weld points, e.g. spot welds 55, whereby thestrength of the weld is made to increase from an upper edge of the sideclosure to a lower edge of the side closure. In this way, the weld 21which forms the fixed attachment can be easily opened at the top edge,but still provides the overall required strength and the security tohold the prefastened product on the wearer. Additionally, this type ofweld avoids the need for use of an intermittent tugging force beingapplied to open the weld when a helper removes the product from a childfor example, which is typically the case with welds which are of thegenerally the same strength along the majority of their length. Thestrength is made to increase in FIG. 16 by using for example larger weldareas and/or increasing the proximity of adjacent weld points as seen ina direction moving from the upper edge to the lower edge.

Various alternative forms of welds 21, 22 may be used to form the fixedattachment between the side flaps, in which a pattern of weld bondingpoints is used (e.g. such as bonding points in the form of spot welds 55as in FIG. 16). A “welded area” can be defined as being the smallestrectangle which encloses all the individual surface areas of the weldbonding points. In order to provide superior opening properties of theweld when desired, the combined individual surface areas of all thebonding points in a welded area should preferably be made to be lessthan approximately 50% of the welded area as defined by the rectangle.This may also be used in the case shown in FIG. 16 and other embodimentsof course. In preferred embodiments, the combined individual surfaceareas may be less than 40%, less than 30%, less than 20% or even lessthan 10% of the welded area defined by the rectangle.

In FIG. 17, the overlapping side panels 8, 12 and 6 are again depictedand a distance “b” has been indicated. The distance “b” is the totaloverlapping width of the two laterally outer end edges 44 and 48 of therear and front side panels respectively. This distance “b” shouldpreferably lie between approximately 0.5 cm and 4 cm, more preferablybetween 0.5 cm and 3 cm, and even more preferably, between 0.5 cm and 2cm. Similarly, the width “c” of the second portion 12 should preferablybe greater than 50% of the overlapping width “b”. In such a way, theamount of elastic material which is not active elastically is minimised.

FIG. 17 also indicates a further distance “d” between edge 44 and thelaterally outer edge of element 10 attached to second portion 12. Thisdistance may be defined as a gripping distance “d”. The grippingdistance is the distance which can be used to grip the end of the secondportion in order to open the reclosable fastening (formed by members 10and 18 or 10 and 46 for example) between front and rear side panels.Distance “d” should preferably be less than 7 mm in order to preventyounger users from trying to open the reclosable fastening. To provideadditional protection against opening a gripping distance of less than 5mm or even less than 3 mm can be used. However, different levels ofopening force should be observed in order to provide child safetyfeatures yet still allow opening in a reliable manner by most adulthelpers, and in a comfortable manner for the wearer.

Experiments on this matter have shown that a child-safe closure can beproduced when a gripping distance of up to 7 mm is used, wherein thereclosable fastening should have an opening force against peeling ofabove 4 N, preferably above 6 N, more preferably above 8 N and even morepreferably above 10 N. With a gripping distance below 3 mm, it ispreferable to avoid an opening force above 10 N. However, at the sametime, the opening peeling force on both the reclosable attachment andalso the weld 21 should preferably not exceed 20 N, otherwise the weareris subjected to an intermittent tugging force being applied in order toopen the reclosable fastening and/or weld 21, which is clearlyunpleasant. Below 20 N, it has now been shown that such intermittenttugging forces are minimised if not entirely avoided, yet at the sametime still provide the required level of force for a safe closure. Evenmore preferred are arrangements where the maximum opening force is below15 N.

In order to measure the forces required to open a joint in peel (i.e.using peel forces), the test method as illustrated in the steps of FIG.18( a) and FIG. 18(b) is used. The two parts of the closure (e.g. sideflap 6 and second portion 12) are attached together e.g. by thereclosable fastening, and a weight is attached to one of the parts e.g.by being clamped to the part over its width. The gripping distanceportion “d” is then gripped and lifted slowly and smoothly, in such away that no jerky movements cause the reclosable joint to separate. Ifthe weight can be lifted and the joint maintained in the situation shownin FIG. 18( b) for more than 30 seconds, it is judged that the joint cansupport the weight and thus meets a particular level of force determinedby the weight. Whilst test machines could be employed to carry out thistest, it is important to realise that the test should correspond as faras possible to a real-life situation and thus the test explained aboveis not only reliable and repeatable but is preferred over any machinetest method.

FIG. 19 shows a further embodiment of the invention in which increasedchild safety is provided by arranging one or more additional welds 56 atthe outer edge 44 of the rear side flap (i.e. at the outer edge of thesecond portion 12 thereof, in this embodiment). These welds 56 inparticular give the appearance of being permanently closed and soprovide a psychological as well as a physical obstruction for a childuser.

In the aforegoing, a number of embodiments have been described in orderto illustrate different aspects of the invention. It is however to beunderstood that the individual features of one embodiment may however beused with, or in place of, features of another embodiment. Inparticular, features shown primarily in embodiments of the product perse are clearly to be understood as being included as additional featuresor alternative features in the method of the invention.

Further embodiments of the product and variations of the method will bereadily understood by the skilled person upon reading the aforegoing andare intended to be encompassed within the scope of the invention asdefined by the appended claims.

1. A prefastened absorbent product, said absorbent product comprising: arear portion, a front portion, and a crotch portion extendingtherebetween, wherein said rear portion includes at least two rear sideflaps, each presenting an inner surface and an outer surface, and saidfront portion includes at least two front side flaps, each presenting aninner surface and an outer surface, the rear and front portions eachincludes a waist edge extending in a lateral direction of the absorbentproduct, a releasable fastening means, wherein one member of saidreleasable fastening means is disposed on an end portion of each of saidrear side flaps and is disposed on each of said front side flaps,respectively, the members of said releasable fastening means on saidfront and said rear side flaps, respectively, being in contact with oneanother to thereby form a reclosable connection therebetween, whereineach of said front side flaps is fixedly attached by a weld to arespective one of said rear side flaps in an overlapping relationshipsuch that the outer surface of each one of said front side flaps liesagainst the inner surface of each respective rear side flap, wherein theweld in each of said rear side flaps lies inwardly along the lateraldirection with respect to the releasable fastening means positioned onsaid respective rear side flap such that the overlapping relationshipbetween the end portion of said rear side flap and said front side flapis defined between at least the releasable fastening means and the weld,wherein at least a part of the weld in each of said rear side flapsoverlays the releasable fastening means positioned on said respectiverear side flap, when viewed in a lateral direction of the absorbentproduct and from a laterally outer edge of said respective rear sideflap, wherein each of said front and said rear side flaps includes anelastic portion, and said weld is positioned proximate a laterally outeredge of the elastic portion of at least one of said front and said rearside flaps, and wherein said rear side flaps each comprise a firstportion fixedly attached to an absorbent product chassis member at afirst attachment location, and a second portion fixedly attached to saidfirst portion at a second attachment location, said second attachmentlocation being positioned laterally outward, with respect to said rearportion, of said first attachment location, wherein one said member ofsaid releasable fastening means is fixedly attached to said secondportion and said first portion includes the elastic portion of said rearside flap.
 2. The prefastened absorbent product according to claim 1,wherein said front side flaps and said rear side flaps are fixedlyattached to each other by said weld along an area of attachmentextending as an elongate welded area between an upper edge and a loweredge of at least one of said front side flaps and said rear side flaps.3. The prefastened absorbent product according to claim 2, wherein saidelongate welded area extends generally parallel to a longitudinal axispassing generally through the middle of the front and rear portions. 4.The prefastened absorbent product according to claim 1, wherein saidelastic portions of at least one of said front side flaps and said rearside flaps are formed from an elastic laminate construction, saidelastic laminate construction being formed with non-woven material on aninner and an outer surface thereof.
 5. The prefastened absorbent productaccording to claim 1, wherein said second portion is inelastic and isstiffer in bending than said first portion.
 6. The prefastened absorbentproduct according to claim 1, wherein said second attachment locationlies laterally outward, with respect to said rear portion, of said weld.7. The prefastened absorbent product according to claim 1, wherein saidreleasable fastening means comprises a first member on said rear sideflaps and a second member on said front side flaps cooperating with saidfirst member to allow releasable attachment, said second membercomprising an external surface of one of said front side flaps.
 8. Theprefastened absorbent product according to claim 7, wherein an entiretyof said second portion of the rear side flap is located laterallyoutward of said weld, with respect to said rear portion.
 9. Theprefastened absorbent product according to claim 1, wherein said weldcomprises a peelable weld, such that the front side flap may be peeledapart from the rear side flap at said weld.
 10. The prefastenedabsorbent product according to claim 1, further comprising a line ofweakening arranged in each of said front side flaps at a locationlaterally inward, with respect to said front portion, of said weld. 11.The prefastened absorbent product according to claim 1, wherein theabsorbent product is formed as a disposable pants diaper.
 12. Aprefastened absorbent product, said absorbent product comprising: anabsorbent chassis member including a rear portion, a front portion, anda crotch portion extending therebetween, wherein said rear portionincludes at least two rear side flaps, each having an inner surface andan outer surface, and said front portion includes at least two frontside flaps, each having an inner surface and an outer surface, each ofsaid front and said rear side flaps including an elastic portion, therear and front portions each includes a waist edge extending in alateral direction of the absorbent product, a releasable fasteningmechanism, wherein each of said rear side flaps carries one member ofsaid releasable fastening mechanism adapted to releasably engage withcorresponding members on each of said front side flaps, respectively,thereby forming a reclosable connection between said rear side flaps andsaid front side flaps, wherein each of said front side flaps is fixedlyattached at a seal location to a respective one of said rear side flapsin an overlapping relationship such that the outer surface of each ofsaid front side flaps lies against the inner surface of each respectiverear side flap, wherein said seal location of said rear side flap liesinwardly along the lateral direction with respect to the releasablefastening mechanism positioned on said respective rear side flap, suchthat the overlapping relationship between said rear side flap and saidfront side flap is defined between at least the releasable fasteningmeans and the seal location, wherein each of said rear side flapsincludes at least a first portion and a second portion, said firstportion being fixedly attached to said chassis member at a firstattachment location, and said second portion being fixedly attached tosaid respective first portion at a second attachment location on saidouter surface of said rear side flap, said second attachment locationbeing disposed laterally outwardly from said first attachment location,wherein at least a part of the weld in each of said rear side flapsoverlays the releasable fastening means positioned on said respectiverear side flap, when viewed in a lateral direction of the absorbentproduct and from a laterally outer edge of said respective rear sideflap, wherein at least a substantial portion of said first portion isformed of elastic material, and wherein elastic material extends betweensaid first attachment location and said second attachment location. 13.The prefastened absorbent product according to claim 12, wherein saidsecond portion is stiffer than said first portion of said rear sideflap.
 14. The prefastened absorbent product according to claim 13,wherein said second portion is formed of material that is less elasticthan the material of the first portion.
 15. The prefastened absorbentproduct according to claim 14, wherein said rear side flaps comprise anelastic laminate material and said second portion is formed by anelastic lamina of the elastic laminate material.
 16. The prefastenedabsorbent product according to claim 14, wherein said second portion isformed as a U-shaped loop.
 17. The prefastened absorbent productaccording to claim 12, wherein said front side flaps include an externalcovering material forming said corresponding members for releasablyengaging said one member of said releasable fastening mechanism carriedby said rear side flaps.
 18. The prefastened absorbent product accordingto claim 12, wherein each of said front side flaps is fixedly attachedat said seal location to a respective one of said rear side flaps bywelding.
 19. The prefastened absorbent product according to claim 18,wherein said welding comprises a series of weld points.
 20. Theprefastened absorbent product according to claim 12, wherein said seallocation is positioned proximate a laterally outer edge of said elasticportion of at least one of said front side flaps and said rear sideflaps.
 21. The prefastened absorbent product according to claim 12,further comprising a line of weakening in each said front side flap. 22.The prefastened absorbent product according to claim 12, wherein atleast one of said front side flaps and said rear side flaps comprises anelastic laminate.
 23. The prefastened absorbent product according toclaim 12, wherein said second attachment location is disposed laterallyoutward with respect to the seal location.